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46 results on '"Interaction rule"'

1. Influence of depth thresholds and interaction rules on the burst capacity evaluation of naturally corroded pipelines

Author

J. Bao and W. Zhou

Subjects
Pipeline, Naturally occurring corrosion, Burst capacity, Interaction rule, Depth threshold, Engineering (General). Civil engineering (General), TA1-2040
Abstract

Based on 14 naturally corroded full-scale pipe specimens, the present study investigates to what extent a corrosion depth threshold influences the burst capacity of naturally corroded pipelines predicted using the finite element analysis (FEA) and well-known RSTRENG model. The study also employs FEA and RSTRENG to investigate the accuracy and effectiveness of five representative interaction rules, namely the B31G, B31.4, CSA, DNV and CW rules, for combining individual naturally-occurring corrosion anomalies into clusters. The analysis results indicate that applying a corrosion depth threshold of 10% of the pipe wall thickness (t) (i.e. any corrosion depths < 10%t are ignored) has a negligible impact on the predicted burst capacity. Furthermore, the CSA interaction rule is considered the most effective among the five interaction rules investigated in that it captures the most critical region of a corroded area without resulting in very large corrosion clusters that are time-consuming to identify and analyze.

Published
2021
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2. Cellular Automata Ants

Author

Bitsakidis, Nikolaos P., Dourvas, Nikolaos I., Chatzichristofis, Savvas A., Sirakoulis, Georgios Ch., Zelinka, Ivan, Series editor, Adamatzky, Andrew, Series editor, and Chen, Guanrong, Series editor

Published
2017
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3. Agent-Based Models as Markov Chains

Author

Banisch, Sven, Abarbanel, Henry, Series editor, Braha, Dan, Series editor, Érdi, Péter, Series editor, Friston, Karl, Series editor, Haken, Hermann, Series editor, Jirsa, Viktor, Series editor, Kacprzyk, Janusz, Series editor, Kaneko, Kunihiko, Series editor, Kelso, Scott, Series editor, Kirkilionis, Markus, Series editor, Kurths, Jürgen, Series editor, Menezes, Ronaldo, Series editor, Nowak, Andrzej, Series editor, Qudrat-Ullah, Hassan, Series editor, Reichl, Linda, Series editor, Schuster, Peter, Series editor, Schweitzer, Frank, Series editor, Sornette, Didier, Series editor, Thurner, Stefan, Series editor, and Banisch, Sven

Published
2016
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6. On Generalized Communicating P Systems with One Symbol

Author

Csuhaj-Varjú, Erzsébet, Vaszil, György, Verlan, Sergey, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Gheorghe, Marian, editor, Hinze, Thomas, editor, Păun, Gheorghe, editor, Rozenberg, Grzegorz, editor, and Salomaa, Arto, editor

Published
2011
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7. The Human-Provided Services Framework

Author

Schall, Daniel, Truong, Hong-Linh, Dustdar, Schahram, Dustdar, Schahram, editor, Schall, Daniel, editor, Skopik, Florian, editor, Juszczyk, Lukasz, editor, and Psaier, Harald, editor

Published
2011
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11. Efficient Semantic Event Processing: Lessons Learned in User Interface Integration

Author

Paulheim, Heiko, Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Doug, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Aroyo, Lora, editor, Antoniou, Grigoris, editor, Hyvönen, Eero, editor, ten Teije, Annette, editor, Stuckenschmidt, Heiner, editor, Cabral, Liliana, editor, and Tudorache, Tania, editor

Published
2010
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12. Conformon P Systems and Topology of Information Flow

Author

Frisco, Pierluigi, Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Doug, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Păun, Gheorghe, editor, Pérez-Jiménez, Mario J., editor, Riscos-Núñez, Agustín, editor, Rozenberg, Grzegorz, editor, and Salomaa, Arto, editor

Published
2010
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13. Interaction-Based Models of Computation

Author

Fernández, Maribel, Mackie, Ian, editor, Abramsky, Samson, editor, Hankin, Chris, editor, Kozen, Dexter, editor, Pitts, Andrew, editor, Nielson, Hanne Riis, editor, Skiena, Steven, editor, Stewart, Ian, editor, Zhang, David, editor, and Fernández, Maribel

Published
2009
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14. Multi-level Network Analysis of Multi-agent Systems

Author

Iravani, Pejman, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Goebel, Randy, editor, Siekmann, Jörg, editor, Wahlster, Wolfgang, editor, Iocchi, Luca, editor, Matsubara, Hitoshi, editor, Weitzenfeld, Alfredo, editor, and Zhou, Changjiu, editor

Published
2009
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16. Infinite Hierarchies of Conformon-P Systems

Author

Frisco, Pierluigi, Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Hoogeboom, Hendrik Jan, editor, Păun, Gheorghe, editor, Rozenberg, Grzegorz, editor, and Salomaa, Arto, editor

Published
2006
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17. Zooming Multi-Agent Systems

Author

Molesini, Ambra, Omicini, Andrea, Ricci, Alessandro, Denti, Enrico, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Dough, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Müller, Jörg P., editor, and Zambonelli, Franco, editor

Published
2006
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18. A Model for Interaction Rules to Define Governance Policies in Collaborative Environments

Author

Camolesi, Luiz, Jr., Martins, Luiz Eduardo G., Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Dough, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Shen, Wei-ming, editor, Chao, Kuo-Ming, editor, Lin, Zongkai, editor, Barthès, Jean-Paul A., editor, and James, Anne, editor

Published
2006
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19. Enabling Autonomic Grid Applications: Requirements, Models and Infrastructure

Author

Parashar, M., Li, Z., Liu, H., Matossian, V., Schmidt, C., Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Babaoglu, Ozalp, editor, Jelasity, Márk, editor, Montresor, Alberto, editor, Fetzer, Christof, editor, Leonardi, Stefano, editor, van Moorsel, Aad, editor, and van Steen, Maarten, editor

Published
2005
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20. Nature-Inspired Computations Using an Evolving Multi-set of Agents

Author

Krishnamurthy, E. V., Murthy, V. K., Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Wang, Lipo, editor, Chen, Ke, editor, and Ong, Yew Soon, editor

Published
2005
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21. Using Inductive Rules in Medical Case-Based Reasoning System

Author

Shi, Wenqi, Barnden, John A., Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Carbonell, Jaime G., editor, Siekmann, Jörg, editor, Gelbukh, Alexander, editor, de Albornoz, Álvaro, editor, and Terashima-Marín, Hugo, editor

Published
2005
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22. Facilitating the Specification Capture and Transformation Process in the Development of Multi-agent Systems

Author

Filho, Aluízio Haendchen, Caminada, Nuno, Haeusler, Edward Hermann, von Staa, Arndt, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Dough, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Carbonell, Jaime G., editor, Siekmann, Jörg, editor, Hinchey, Michael G., editor, Rash, James L., editor, Truszkowski, Walter F., editor, and Rouff, Christopher A., editor

Published
2005
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23. Enhancing Cellular Automata by an Embedded Generalized Multi-layer Perceptron

Author

Trunfio, Giuseppe A., Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Duch, Włodzisław, editor, Kacprzyk, Janusz, editor, Oja, Erkki, editor, and Zadrożny, Sławomir, editor

Published
2005
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24. Simulating Complex Dynamical Systems in a Distributed Programming Environment

Author

Krishnamurthy, E. V., Krishnamurthy, Vikram, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Dough, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, Jin, Hai, editor, Gao, Guang R., editor, Xu, Zhiwei, editor, and Chen, Hao, editor

Published
2004
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25. A MzScheme Implementation of Transition P Systems

Author

Balbontín Noval, Delia, Pérez Jiménez, Mario J., Sancho Caparrini, Fernando, Goos, G., editor, Hartmanis, J., editor, van Leeuwen, J., editor, PĂun, Gheorghe, editor, Rozenberg, Grzegorz, editor, Salomaa, Arto, editor, and Zandron, Claudio, editor

Published
2003
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27. Influence of depth thresholds and interaction rules on the burst capacity evaluation of naturally corroded pipelines

Author

Wenxing Zhou and J. Bao

Subjects
Fluid Flow and Transfer Processes, Materials science, Interaction rule, business.industry, Mechanical Engineering, Depth threshold, Burst capacity, 020101 civil engineering, 02 engineering and technology, Structural engineering, Engineering (General). Civil engineering (General), Finite element method, 0201 civil engineering, Corrosion, Pipeline transport, 020303 mechanical engineering & transports, 0203 mechanical engineering, Pipeline, Naturally occurring corrosion, TA1-2040, Safety, Risk, Reliability and Quality, Wall thickness, business, Energy (miscellaneous)
Abstract

Based on 14 naturally corroded full-scale pipe specimens, the present study investigates to what extent a corrosion depth threshold influences the burst capacity of naturally corroded pipelines predicted using the finite element analysis (FEA) and well-known RSTRENG model. The study also employs FEA and RSTRENG to investigate the accuracy and effectiveness of five representative interaction rules, namely the B31G, B31.4, CSA, DNV and CW rules, for combining individual naturally-occurring corrosion anomalies into clusters. The analysis results indicate that applying a corrosion depth threshold of 10% of the pipe wall thickness (t) (i.e. any corrosion depths < 10%t are ignored) has a negligible impact on the predicted burst capacity. Furthermore, the CSA interaction rule is considered the most effective among the five interaction rules investigated in that it captures the most critical region of a corroded area without resulting in very large corrosion clusters that are time-consuming to identify and analyze.

Published
2021

28. Interaction of multiple corrosion defects on burst pressure of pipelines.

Author

Mondal, Bipul Chandra and Dhar, Ashutosh Sutra

Subjects
*PIPELINE maintenance & repair, *CRACKING of pipelines, *PIPELINE failures, *FINITE element method, PIPELINE corrosion
Abstract

The strength of pipeline with multiple corrosion patches depends on the number of corrosion patches within an area on the pipe surface, the locations of corrosion patches along the longitudinal and circumferential directions of the pipe. In this paper, the strength and deformation characteristics of corroded pipeline are investigated using finite element analysis. Pipes with different diameters and different depths of corrosion patches are considered. The spacing of the corrosion patches is varied along longitudinal, diagonal, and circumferential directions of the pipes. The study shows that the limiting spacing for interaction of corrosion patches depends predominantly on pipe wall thickness, corrosion depth, and the location of the defects. The diameter of the pipe has some influence on the interaction for large diameter pipes. A new interaction rule for the limiting spacing for interaction is developed for longitudinally spaced corrosion patches. For circumferentially spaced corrosion patches, the ASME recommendation for the limiting spacing is found to be reasonable. [ABSTRACT FROM AUTHOR]

Published
2017
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29. Ontogeny of collective behavior reveals a simple attraction rule.

Author

Hinz, Robert C. and de Polavieja, Gonzalo G.

Subjects
*MORPHOMETRICS, *BIRDS, *EMBRYOLOGY, *PROTOPLASM, *ATTRACTION-selection-attrition model
Abstract

The striking patterns of collective animal behavior, including ant trails, bird flocks, and fish schools, can result from local interactions among animals without centralized control. Several of these rules of interaction have been proposed, but it has proven difficult to discriminate which ones are implemented in nature. As a method to better discriminate among interaction rules, we propose to follow the slow birth of a rule of interaction during animal development. Specifically, we followed the development of zebrafish, Danio rerio, and found that larvae turn toward each other from 7 days postfertilization and increase the intensity of interactions until 3 weeks. This developmental dataset allows testing the parameter-free predictions of a simple rule in which animals attract each other part of the time, with attraction defined as turning toward another animal chosen at random. This rule makes each individual likely move to a high density of conspecifics, and moving groups naturally emerge. Development of attraction strength corresponds to an increase in the time spent in attraction behavior. Adults were found to follow the same attraction rule, suggesting a potential significance for adults of other species. [ABSTRACT FROM AUTHOR]

Published
2017
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39. Combinatorial Methods in Security Testing.

Author

Simos, Dimitris E., Kuhn, Rick, Voyiatzis, Artemios G., and Kacker, Raghu

Subjects
*COMPUTER security, *COMBINATORICS, *COMPUTER software security, *COMPUTER network protocols, *INTERNET of things
Abstract

Combinatorial methods can make software security testing much more efficient and effective than conventional approaches. [ABSTRACT FROM PUBLISHER]

Published
2016
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40. Effect of interaction between corrosion defects on failure pressure of thin wall steel pipeline.

Author

Li, Xin, Bai, Yu, Su, Chenliang, and Li, Mingshu

Subjects
*STEEL, *FINITE element method, *FRACTURE mechanics, *PRESSURE, *PIPELINES, *CORROSION resistance
Abstract

The finite element models of corroded pipelines with colony of defects composed of two longitudinal or circumferential aligned defects, and four defects arranged in rhombus shape are established and validated, respectively. Considering the different longitudinal and circumferential spacings between defects, the cases related to 13 types of colony of defects are computed. Based on the ratio of failure pressure of each case to the failure pressure of corresponding base case, the interaction between defects is determined. Then a new interaction rule is proposed. Compared with the performance of DNV RP F101, the API 579, the BS 7910, the Kiefner and Vieth, and the Pipeline Operator Forum (POF) interaction rules which are applied to FE cases, the proposed rule could satisfactorily identify whether or not the interaction between defects occurs. [ABSTRACT FROM AUTHOR]

Published
2016
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42. Finite Element Analyses and Random Field Modeling of Naturally Corroded Underground Energy Pipelines

Author

Bao, Ji

Subjects
Structural Engineering, random field analysis, corrosion anomaly class, interaction rule, Underground pipeline, finite element analysis, naturally occurring corrosion features, Civil Engineering
Abstract

Metal-loss corrosion is one of the major threats to the integrity of oil and natural gas pipelines. The Fitness-For-Service (FFS) assessment is commonly carried out to demonstrate the integrity of the corroded pipelines. The naturally occurring corrosions on the external surfaces are irregularly shaped three-dimensional features. Due to the geometric complexity of the natural corrosion features, the research of FFS assessment in the previous studies always employed the pipe segments containing artificially induced corrosion features. However, since artificial features are in general regular-shaped, e.g. cubic or semi-ellipsoidal, they do not capture geometric characteristics of naturally occurring corrosions. The thesis develops a finite element model and a random field based corrosion model to deal with five issues regarding the FFS assessment of pipe segments containing naturally occurring corrosion features. The first study develops a three-dimensional finite element model to simulate the full-scale burst tests of pipe segments containing real corrosion features. The finite element model, as well as the RSTRENG model, is used to study the impact of the depth threshold and five commonly used interaction rules on the burst capacity predictions of naturally corroded pipe segments. This study recommends the optimal depth threshold values and interaction rules to evaluate the burst capacity of corroded pipelines in the practical FFS assessment. The second study investigates the impact of corrosion anomaly classes on the predictive accuracy of the B31G, B31G-M, Shell92, PCORRC, PCORRC-M, CSA and RSTRENG models, based on 897 corrosion anomalies on 16 naturally corroded pipe specimens removed from in-service pipelines. The 897 corrosion anomalies are classified into seven classes, namely pin hole, axial slotting, axial grooving, circumferential slotting, circumferential grooving, pitting and general corrosion, based on the Pipeline Operators Forum (POF) anomaly classification system. The seven burst capacity models and finite element analyses (FEA) are employed to evaluate the burst capacities of the corrosion anomalies. The accuracies of the burst capacity models are assessed and compared based on the FEA-to-model predicted burst capacity ratios for different classes of anomalies. The third study proposed a modified RSTRENG (RSTRENG-M) model to evaluate the burst capacity of corroded pipelines by employing the riverbed profile of corrosion features. The riverbed profile consists of representative corrosion depths at a collection of circumferential profiles of the corrosion feature and takes into account the influence on the burst capacity of the maximum corrosion depth and overall metal loss associated with the circumferential profile. Based on full-scale burst tests of 16 naturally corroded pipe specimens and 44 specimens containing artificially induced corrosion features, RSTRENG-M is shown to be more accurate than the RSTRENG model, particularly for corrosion features with complex morphologies, comparable to the Psqr model in terms of accuracy but more advantageous in terms of computational efficiency. An empirical equation is also developed to estimate the representative depth for a given circumferential profile directly from the corresponding maximum depth to facilitate the application of RSTRENG-M in the context of the inline inspection data. The fourth study proposes a random field model to characterize the corrosion depth on the external surface of buried oil and gas pipelines. The model addresses the intermingling of corroded and corrosion-free areas on the pipe surface by using a latent homogeneous Gaussian random field and a spatial position-dependent threshold associated with the latent Gaussian field. High-resolution corrosion measurement data obtained from corroded pipe segments removed from in-service pipelines are used to estimate parameters of the proposed model, including the probability of corrosion at a given point, marginal distribution of the nonzero corrosion depth and correlation structure of the latent Gaussian field. A comparison of simulated and measured corrosion fields suggests that the proposed model is able to capture the characteristics of naturally-occurring corrosion field on the pipe surface. The fifth study combines the FEA model developed in the second study with the random field-based corrosion model presented in the fourth study to analyze the simulated naturally occurring corrosion features (i.e. synthetic corrosion features) in large quantity to further validate the RSTRENG-M model. For comparison, the predictive accuracies of RSTRENG, CSA, CPS, Psqr and DNV are also investigated based on the FEA results of the synthetic corrosion features. The impact of length and maximum depth of corrosion feature on the predictive accuracies of the six semi-empirical models are also presented.

Published
2020

43. The direct strength method for combined bending and web crippling of second-generation trapezoidal steel sheeting.

Author

Willems, D.W.C., Hofmeyer, H., Snijder, H.H., and Schafer, B.W.

Subjects
*SHEET steel, *COLD-formed steel, *TORQUE, *BENDING moment, *MECHANICAL buckling, *EIGENVALUES, *FLANGES
Abstract

Second-generation trapezoidal sheeting, characterised by longitudinal stiffeners in webs and flanges, is loaded near a support by a concentrated force and a bending moment. Currently, design codes predict related failure by: (a) determining the ultimate bending moment via the effective width approach or the Direct Strength Method (DSM); (b) finding the web crippling load via a curve-fitted formula; and (c) using an interaction rule to take into account the load combination. However, the effective width approach is quite complex to use for many longitudinal stiffeners, and the accuracy of the design codes is subject to improvement. Moreover, nowadays the DSM provides a consistent and well-established method to predict ultimate loads for cold-formed steel structures. Therefore, in this paper the application of the DSM for combined bending and web crippling of second-generation sheeting is investigated. First, to create a set of numerical experiments, an internationally representative set of second-generation trapezoidal sheeting types is found, and these types are used to design numerical three-point bending experiments with relevant span lengths and load bearing plate widths. Then, finite element models are developed and verified, and used to predict the buckling, yield, and ultimate loads for the set of numerical experiments. Additionally, all simulations are also carried out for pure bending, and (Interior One Flange) IOF and (Interior Two Flange) ITF web crippling cases. With the resulting data, an explicit DSM approach is developed, fitted to the data of the three-point bending simulations, which predicts the ultimate load for combined actions directly. Hereafter, also an interaction DSM approach is studied, which first predicts the ultimate bending moment by the DSM (by fitting the pure bending simulations), then the web crippling load by the DSM (by fitting either the IOF or ITF simulations), and then uses a classic interaction rule for the load combination. The explicit and implicit DSM approaches perform equally well, with a Coefficient of Variation (CoV) equal to 0.13. As most commercially available sheeting has been incorporated, and the DSM approaches allow for sections with an arbitrarily number of stiffeners in the web (different from the current design codes), it is recommended to include the DSM in future code revisions. The interaction DSM approach resembles the current design rules most and may therefore be preferred; however, the explicit approach is more direct and certainly deserves consideration too. • Currently available second-generation sheeting organised and studied. • FE simulations provide DSM data for Eigenvalues, yield load, ultimate load. • No need to model stiffener corners. • Both explicit and implicit DSM show COV = 0.13. • TF Eigenvalues or yield loads do not improve web crippling results. [ABSTRACT FROM AUTHOR]

Published
2021
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46. Identification of Distributed Systems with Logical Interaction Structure

Author

Simone Martini, Adriano Fagiolini, Antonio Bicchi, Laura Giarre, Martini, S, Fagiolini, A, Giarré, L, and Bicchi, A

Subjects
Partial knowledge, Theoretical computer science, Interaction rule, Distributed computing, Binary number, Class (philosophy), Individual dynamic, Algebraic normal form, Logical function, Algebraic normal forms, Binary functions, Cooperating systems, Distributed systems, Individual agent, Individual dynamics, Interaction rules, Interaction structures, Logical functions, Logical maps, Lower approximation, Network structures, Networked systems, Real systems, Structure identification, Truth tables, Binary function, Settore ING-INF/04 - Automatica, Logical map, Mathematics, Cooperating system, Structure (mathematical logic), Networked system, Truth table, Mobile robot, Real system, Parameter identification problem, Identification (information), Interaction structure, Distributed system, Network structure
Abstract

This paper focuses on the structure identification problem for a class of networked systems, where the interaction among components or agents is described through logical maps. In particular, agents are heterogeneous cooperating systems, i.e. they may have different individual dynamics and different interaction rules depending on input events. While we assume that the individual agents' dynamics are known, each agent has partial knowledge of the logical map encoding the interaction of another agent with its neighbors. Based on the so-called algebraic normal form for binary functions, we present a technique by which the network structure described by a logical function can be dynamically estimated as its truth table is observed. The estimated map is a lower approximation of the real one, which coincides with it as soon as the truth table is entirely observed. Application of the proposed technique to a real system, where agents are mobile robots whose motion depends on logical conditions on their neighborhood, is finally presented.

Published
2012

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